Apple tree prunning

[apple guy]

Hi all, I bought a house last autumn with this apple tree full of apples in the back garden. The neighbours informed me that the garden and trees had not been touched for years and was in a sorry state. I don't really know where to start with prunning it and am hoping for some advice. Please see photos below.
Thanks in advance

 

[Chuck]

Hi all, I bought a house last autumn with this apple tree full of apples in the back garden. The neighbours informed me that the garden and trees had not been touched for years and was in a sorry state. I don't really know where to start with prunning it and am hoping for some advice. Please see photos below.
Thanks in advanceView attachment 50829

This video sums it up better than I can explain